Locking plier wrench

ABSTRACT

AN ARTICULATED LINK OPERATED WRENCH HAVING A FIXED AND SLIDEABLE JAW WHEREIN THE CENTER LINE OF THE WRENCH BODY IS SUBSTANTIALLY COINCIDENT WITH THE LONGITUDINAL CENTER LINE OF THE LINKAGES AND THE SLIDEABLE JAW AND WHEREIN AN EXTENSION OF THE CENTER LINE BISECTS THE INTERSPACE BETWEEN THE FIXED AND SLIDEABLE JAW.

Feb. 23, 1971 LANDEN 3,564,956

LOCKING PLIER WRENCH Filed Feb. 21, 1968 Fiyj .4-

INVENTOR are/v.4 80 LA van/Y ATTORNEY United States Patent 01 3,564,956 LOCKING PLIER WRENCH Bernard Landen, Rte. 1, Box 54A, Highway 8587, Fountain, Colo. 80817 Filed Feb. 21, 1968, Ser. No. 707,138 Int. Cl. B25b 13/12, 13/16 U.S. Cl. 81-126 2 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to a hand tool and more particularly to a reciprocating jaw wrench having a plier type of handle for gripping and holding a nut, bolt, pipe or other object.

The primary object of this invention is to improve on prior art devices of the same general type by providing a lever and link actuated slideable jaw wrench in which all lines of force are coincident with the handle of the wrench and are applied through the center of the piece being held. The advantages of such a system are quickly seen when it is recognized that all prior art wrenches create clamping forces which produce internal bending moments, either in the handle, jaw or linkages, thus severely limiting the clamping and holding ability of any given structural design.

It is therefore a secondary object of the present invention to describe a combination of working parts which can apply an unexpectedly great amount of clamping force to an object being held with relatively small structural members, that is to say, for a wrench of any given size, the device of this invention can increase the holding force many times over a seemingly similar wrench of the prior art.

A third object of the invention is to provide a wrench having the dual capability of ratchet type operation and locking.

Other and further objects and advantages of the apparatus of the present invention will be made to appear in the following detailed description of a preferred form of the invention taken in conjunction with the accompanying drawings in which:

FIG. 1 is a side elevational view of the wrench showing the jaws in the open position,

FIG. 2 is a side elevational view showing the wrench in the locked position.

FIG. 3 is a cross sectional view taken along lines 3--3 of FIG. 4 and showing the wrench in the gripping position without being locked.

FIG. 4 is a top view of the wrench.

FIG. 5 is a cross sectional view taken along lines 5-5 of FIG. 1.

Referring to the several illustrative views in the drawings, the wrench construction is organized within a body member 3 which, in the preferred form, comprises an elongated channel having a bottom 4 and spaced apart parallel side walls 5. At one end 7 of the body 3 the channel is formed and closed so as to be cylindrical in shape. The inside of the cylinder portion 7 is provided with threads 9 which are adapted to engage the threads of an adjusting bolt 12. The other end of the body 3 is also closed on all sides with a rectangular opening 15 therethrough in which to slidably receive a movable jaw 17. A fixed jaw 19, generally in the shape of a C, is

Bee

integrally attached to the end of the wrench body 3 in such a fashion that a center line passing vertically through the C will be coincident with the longitudinal center axes of the body 3 and the movable jaw 17.

Intermediate the inner end of the adjusting bolt 12 and the interior end of the slideable jaws 17 are two interconnecting and articulating links 20 and 25. Each end of the two links are provided with joints in order to allow pivotal movement of one link with respect to the other in a plane which passes through the longitudinal center line of the body 3 and which plane is parallel to one side 5 of the body channel. The articulating joints preferably comprise disks 28 and 30, integral with the respective ends of links 20 and 25, which are rotatably disposed in cooperating sockets or open sided apertures 29 and 31 in the end of the respective adjacent links or members. A similar joint is provided between the adjusting bolt 12 and the link 20 and comprises a ball 33 integral with the bolt 12 and a cooperating socket 34 in the end of the link 20. It should be noted that the adjusting bolt 12 could be in a dilferent form, as long as it provides longitudinal adjustment of the position of the ball 33 in order to vary the total distance between the fixed jaw and the ball 33.

The operating link 25 is secured to or integral with a plier-type of handle 32 protruding from the link and co-planer therewith. As seen from a comparison of FIGS. 1 and 3, depression of the handle 32 in a direction toward the body 3 wedges the two links 20 and 25 into an aligned position between the movable jaw 17 and the adjusting bolt 12. If the center point of the joint 28, 29 is pressed to a position past the longitudinal center line A, as shown in 'FIG. 2, the jaws 17 of the wrench is then locked in position on the nut 40 and cannot be released without reverse pressure being applied to the handle 32. In the locked position of the wrench, the line of equivalent compression force existing in the slideable jaw 17 and linkages 20 and 25 is coincident with an equivalent tension force in the wrench body 3. This matching of tension and compression forces along a single axis entirely eliminates bending moments in the body of the wrench or in any of the linkages or moving parts. The end result of course is a substantial reduction in the structural requirements of the wrench, or conversely, a quantitive gain in the holding pressure which a wrench of given size and weight can exert.

It should also be noted that the pressure exerted by the jaws is to some extent dependent on the longitudinal position of the adjusting bolt 12. The bolt 12 must be positioned to roughly adjust the space between the slideable and the fixed jaws and may then be more finely adjusted to vary the inter-jaw distance and consequently change the force which must be exerted to compress the links, movable jaw member and nut 40 in order to pass the center of disc 28 over the center line A Obviously, the greater the force which must be exerted to lock the wrench, the greater the holding force.

I The construction of the wrench lends itself to use as a ratchet device. A coil spring 44 is disposed between the handle 32 and the outside edge of link 20 in such a manner that the spring bias tends to force the handle 32 and the link 20 apart, as shown in FIG. 1. If the spring is allowed to so act, the linkages 20 and 25 will be articu-* lated into a foreshortened position where the slideable jaw 17 is withdrawn into the body 3, thus enlarging the distance between jaws. When it is desired to use the wrench as a ratchet, the stop lever 47 is pivotally extended, as illustrated in FIG. 3, so that the handle 32 cannot be compressed far enough to lock the wrench, that is, the center of the disk 28 will approach the center line A but cannot cross it. The stop lever 47 is sized and dimensioned, as shown in FIG. 3, so that when it is rotated into its operating position there is sufficient frictional force between the bottom of the lever and the handle 32 in which the lever is mounted so that the forces present on the lever when it abuts against the link 20' will not move it out of its operating position. With the handle in the compressed position, the nut 40 can be turned. To get a new bite on the nut 40, pressure on the handle 32 is momentarily released and the bias pressure of the ratchet spring 44 will open the jaws to allow the wrench body to be rotated to a new angular position on the nut 40. Unlike most ratchet devices, the opening of the jaws does not depend on the stability of the nut, that is, the nut itself need not exert any force on the ratchet device in order that it will operate. The only force necessary to open the jaws is that provided by the spring 44.

Even when operating as a ratchet device where there is no over the center locking, it will be noted that the advantages of the aligned forces are still present and available.

Having thus described the several useful and novel features of the Locking Plier Wrench of the present in vention in connection with the accompanying drawings, it will be seen that the many worthwhile objectives for which it was designed have been achieved. Although but a few of the several possible embodiments of the invention have been illustrated and described herein, we realize that certain additional modifications may well occur to those skilled in the art within the broad teaching thereof; hence, it is my intention that the scope of protection atforded hereby shall be limited only insofar as said limitations are expressly set forth in the appended claims.

I claim:

1. A wrench, comprising in combination:

an elongated hollow body having a fixed jaw member on one end thereof and a longitudinally adjustable end member on the other end thereof;

a slideable jaw within the said body and disposed in opposing relation to the said fixed jaw so that the longitudinal center axis of the slideable jaw is substantially coincident with the longitudinal center axis of said body and where an extension of said coincident axes substantially bisect the interspace between the said fixed and movable jaws;

first and second link members intermediate the slideable jaw and the said adjustable end member and whose longitudinal center axes are substantially coincident with the said longitudinal axis of the body when the links are aligned;

articulating joint means interconnecting the said link members, interconnecting the adjustable end member and the first link member and interconnecting the slidable jaw and the second of said link members;

a handle attached to the said second one of said link members; and

a compression spring disposed between the handle and the first link member wherein said spring bias tends to separate said handle and link.

2. The wrench of claim 1 and further including a stop member pivotally mounted on said handle and adapted to limit the interspace between the handle and the first link member.

References Cited UNITED STATES PATENTS 1,810,938 6/1931 Baash et al 81-126X 372,080 10/1887 Mitchell 1--363X 2,471,734 5/1949 Fischer 81-363X 2,536,463 1/1951 Ratliff 81126 2,577,888 12/1951 Greathouse 8l126 ANDREW R. JUHASZ, Primary Examiner L. GILDEN, Assistant Examiner US. Cl. X.R. 81175, 363 

